<!DOCTYPE html>
<html lang="">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title></title>
</head>

<body>
    <div id="main">
</div>
<script type="text/script">
    var div=document.getElemenetById("main");

    div.innerHTML="<p>加内容</p>";

</script>
</body>
</html>
